mo-ta モーター

October 7, 2006

Can I use the END output signal as a trigger to turn on/off the magnetic brake via a relay?

Filed under: Stepper Motors — mota @ 2:57 am

Yes, but you need to have a programmed delay before the motion starts and after the motion ends. You can do this through the PLC’s timer function, or if using the SC8800, feed the END output signal from the AlphaStep driver into one of the SC8800’s inputs. From there, you can use conditional statements, e.g., If IN1=1, DELAY=0.2, MI, etc. Remember, the END signal comes on only when the deviation counter (the difference between the pulse counter and rotor position counter) is within +/- 1.8° of the commanded position. So pulses may have stopped, but the rotor is lagging due to inertia, velocity filter setting, etc. If you didn’t compensate for this slight delay, the brake would come on right after the pulse train stops, and that would lead to premature brake wear and possibly inaccurate positioning.

Leave a Comment »

No comments yet.

RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Blog at

%d bloggers like this: